allocate_trivial_strategy bmaps td owner repl index number:
Allocates blocks for the index range index to index+number-1.
The replication factor is repl. The blocks are allocated in the
passed blockmaps bmaps, and will be assigned to owner.
Tickets are generated for the transaction identified by td.

This is the "trivial" algorithm. It iterates over the index range
and tries to allocate each block separately, without taking advantage
of the range. This algorithm should not be used anymore; it is
kept in the code base purely for documentation purposes.